Effects of decontamination solutions on the surface of titanium: investigation of surface morphology, composition, and roughness

AIM: To investigate the impact of treatments used to detoxify dental implants on the oxide layer morphology and to infer how changes in morphology created by these treatments may impact re-osseointegration of an implant. MATERIALS AND METHODS: Pure titanium (cpTi) and the alloy Ti6Al4V were subjected to a series of chemical treatments and mechanical abrasion simulating surface decontamination of dental implants. The morphology and roughness of the surface layer before and after treatment with these solutions were investigated with optical and atomic force microscopy (OM, AFM). The solutions employed are typically used for detoxification of dental implants. These included citric acid, 15% hydrogen peroxide, chlorhexidine gluconate, tetracycline, doxycycline, sodium fluoride, peroxyacetic acid, and treatment with carbon dioxide laser. The treatments consisted of both immersions of samples in solution and rubbing with cotton swabs soaked in solution for 1, 2, and 5 min. Cotton swabs used were analyzed with energy dispersive spectroscopy (EDS). RESULTS: The microscopy investigation showed that corrosion and pitting of the samples were present in both metal grades with immersion and rubbing methods when employing more acidic solutions, which had pH <3. Mildly acidic solutions caused surface discoloration when coupled with rubbing but did not cause corrosion with immersion. Neutral or basic treatments resulted in no signs of corrosion with both methods. EDS results revealed the presence of titanium particles on all rubbing samples. CONCLUSION: It was demonstrated in this study that acidic environments coupled with rubbing are able to introduce noticeable morphological changes and corrosion on the surface of both titanium grades.